Incident Management and Network Performance

This paper describes an investigation into the scope for reducing trip time variability associated with incidents (e.g. accidents), through better incident management. The investigation involved using micro-simulation (S-Paramics) to model incident detection and response in a part of the Auckland (New Zealand) network, which includes a motorway and adjacent parallel arterial roads. The effect of blockages on the motorway or an adjacent arterial road, with and without mitigation (e.g. modifying the SCATS arterial road signal coordination plan, using variable message signing and allowing motorway traffic to use the hard-shoulder), were assessed. It was found that the reductions in the variability of trip times, as a result of implementing mitigation options, were much larger than the reductions in mean trip times.